- int remaining = endptr - ptr;
- uschar header[PIPE_HEADER_SIZE + 1];
- uschar id, subid;
- uschar *endc;
-
- /* Read (first time) or top up the chars in the buffer if necessary.
- There will be only one read if we get all the available data (i.e. don't
- fill the buffer completely). */
-
- if (remaining < required && !finished)
- {
- int len;
- int available = big_buffer_size - remaining;
-
- if (remaining > 0) memmove(big_buffer, ptr, remaining);
-
- ptr = big_buffer;
- endptr = big_buffer + remaining;
- len = read(fd, endptr, available);
-
- DEBUG(D_deliver) debug_printf("read() yielded %d\n", len);
-
- /* If the result is EAGAIN and the process is not complete, just
- stop reading any more and process what we have already. */
-
- if (len < 0)
- {
- if (!eop && errno == EAGAIN) len = 0; else
- {
- msg = string_sprintf("failed to read pipe from transport process "
- "%d for transport %s: %s", pid, addr->transport->driver_name,
- strerror(errno));
- break;
- }
- }
-
- /* If the length is zero (eof or no-more-data), just process what we
- already have. Note that if the process is still running and we have
- read all the data in the pipe (but less that "available") then we
- won't read any more, as "finished" will get set. */
-
- endptr += len;
- remaining += len;
- finished = len != available;
- }
-
- /* If we are at the end of the available data, exit the loop. */
- if (ptr >= endptr) break;
-
- /* copy and read header */
- memcpy(header, ptr, PIPE_HEADER_SIZE);
- header[PIPE_HEADER_SIZE] = '\0';
- id = header[0];
- subid = header[1];
- required = Ustrtol(header + 2, &endc, 10) + PIPE_HEADER_SIZE; /* header + data */
- if (*endc)
- {
- msg = string_sprintf("failed to read pipe from transport process "
- "%d for transport %s: error reading size from header", pid, addr->transport->driver_name);
+ uschar pipeheader[PIPE_HEADER_SIZE+1];
+ uschar *id = &pipeheader[0];
+ uschar *subid = &pipeheader[1];
+ uschar *ptr = big_buffer;
+ size_t required = PIPE_HEADER_SIZE; /* first the pipehaeder, later the data */
+ ssize_t got;
+
+ DEBUG(D_deliver) debug_printf(
+ "expect %lu bytes (pipeheader) from tpt process %d\n", (u_long)required, pid);
+
+ /* We require(!) all the PIPE_HEADER_SIZE bytes here, as we know,
+ they're written in a timely manner, so waiting for the write shouldn't hurt a lot.
+ If we get less, we can assume the subprocess do be done and do not expect any further
+ information from it. */
+
+ if ((got = readn(fd, pipeheader, required)) != required)
+ {
+ msg = string_sprintf("got " SSIZE_T_FMT " of %d bytes (pipeheader) "
+ "from transport process %d for transport %s",
+ got, PIPE_HEADER_SIZE, pid, addr->transport->driver_name);